watchOS 4.2.2 (build 15S5530d) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2017-12-13T21:09:18Z. The update package is 54.88 MB. This is a delta (partial) update that requires 4.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 00aa0edbb0ff905418912b34c12fd9c2edc0bdc3.zip.